Continuous rolling mill



March 31, 1936. w; ROHN CONTINUOUS ROLLING MILL Filed Nov. 14, 1951 2Sheets-Sheet l Fig.

March 31, 1936. w, ROHN 2,036,101

CONTINUOUS ROLLING MILL Filed. Nov. 14, 1951 2 Sheets-Sheet 2 fnvenior:mm

' atente 3i, id

hiidh llllll GNTlUS a J ilhclm hn, Hu-on-thedtllain, Gerry ApplicationNovember lid, ran, denial no. tracts lln Geny November ll'l, i030 2Dias.

"lilllis invention relates to improvements in and relating to continuousrolling mills.

Continuous rolling mills with a separate drive for the separate passeshave already-been dea scribed which enable wires to be rolled in asimple and economical manner down to 1 mm., whereas previous thereto itwas only possible to roll economically down to about 5 mm., and fromthis thickness of wire further reduction had to be 1m effected bydrawing. $uch rolling mechanisms have been found to be of particularadvantage for the treatment of hard material, as for'example specialsteels and rope wires. For material, such as brass or copper, which isworked more easily it has not been possible hitherto to introduce theseconstructions to any considerable extent as these rolling mills arecomparatively expensive so that for materials whicharecapable of beingworked easily drawing to below 5 mm. or below '3 mm. was more economicalduly considering the costs of installing the mills and duly consideringthe costs of the rolling rings.

Closer inspection of the construction of rolling mills shows that thelargest portion of the costs of construction of the rolling mills is dueto the toothed wheel gearing between the separate driving motors and therolling rings, and that the largest portion of the costs of operation isdue to the cost of the comparatively large and heavy rolling rings. Forrolling material of average hardness and for soft material, particularlywhen this is to be rolled at high rolling speeds, it is possible toeffect a reduction of about one-third to one-quarter in the costs ofinstallation and operation by reducing the diameter of the rolling ringsto such an extent that toothed wheel gearing can be omitted between thedriving members and the rolling rings, and that the rolling rings areallowed to operate directly at the speed of rotation of the drivingmembers without intermediate gear wheels. For rolling material ofaverage hardness or for soft material it is sufiicient for the diameterof the rolling rings to be about six times or at most ten times thediameter of the wires to be rolled. In this manner it is suffi 'cientfor rolling 5 mm. wires to use rolling rings having a diameter of 40 to50 mm. and for rolling wires between 2 and 1 mm. to use even rollingrings having a diameter of from 25 to 35 mm. m When the drive iseifected by normal motors having the speed of 1,000 revolutions perminute there are obtained rolling speeds amounting to from 90 to 160 m.per minute, speeds which are regarded as normal for the cold rolling ofmate rial of average hardness.

("Ut- 00 m) For soft material these rolling speeds can be increased totwice and three times that amount,

so that there are used motors having a speed of from 2,000 to 3,000revolutions per minute. In such a form of construction the drivingmembers 0 then constitute the essential portion of the costs ofinstallation, whereas the expense for the additional mechanical devicesonly amount to about one-third of the costs of the motors. in the knownconstructions, however, the mechanical l0 portion of the rolling millsamounts to about three times the cost of the motors which serve asdriving members. It will thus be seen that the costs of installation ofrolling mechanisms according to the invention are considerably re- 1duced, whilst their range of use is extended to a conslderableextent tomaterials which are capabio of being worked more easily, particularlyalso as it is possible to use rolling rings having a diameter of 30 to50 mm. which cost only from 20 1/15 to of the cost of rolling ringshaving a diameter of 125 mm.

According to the particular rolling problem to be solved the inventiveidea as described above can be carried out in practice in various waysas 25 mentioned below and illustrated by the accompanying drawings ofwhich A Fig. l is a side view, partly in section, of a single rollingstation together with its driving memher the supporting bed not beingshown.

Fig. 2 is a sectional side view of a detail of a rolling station inwhich the shafts carrying the rolling rings are coupled together bytoothed wheels.

Fig. 3 shows a further mode of performance of 35 a single station inwhich the rolling rings are mounted on shafts coupled by flexible jointswith the motor shaft.

Figs. 4 and 4a illustrate the bearing of the shafts carrying the rollingring, Fig. 4 being a tit sectional side view and Fig. do a front view ofa rolling station. A

Fig. 5 shows means for positioning the rolls of a station according toFigures i and 4a.

Fig. 0 shows diagrammatically a rolling mill looking in the direction ofrolling. j

Figs. 7 and 7a. show in side and front elevation respectively theconstruction oil a rolling mill in which the driving members consist ofelectric motors each of which is built together with a simple gear trainso as to form a driving unit removable as a whole.

For material which is capable of being worked easily the rolling ringscan be mounted directly in a flying manner on the shafts of the drlveding motors, in which case it may be preferable to make a roller bearingof the motor which is used at the side of the shaft, somewhat heavierthan usual so as to be capable of better withstanding rolling pressures.The additional expenses incurred by such a dimensioning of a motorbearing are extremely small in comparison with the costs which would beincurred if it were necessary to provide a separate bearing for therolls. For rolling material which can be worked easily the secondrolling ring does not require a separate drive but may operate in theknown manner as a. frictionally' driven roller. As the necessary settingrange in multi-roll rolling mechanisms, which always have to carry outthe same operation, need only be very small the setting device for thesecond rolling ring may also be constructed very simply and cheaply.

An example of construction is shown in Figure l of the accompanyingdrawings in which, for the purpose of positioning, the shaft 0 carryingthe second rolling ring is not displaced parallel in the usual manner,but is swung about its end opposite the rolling ring about the point e.With the small positioning limits which are here necessary the angle atwhich the two shafts must be inclined to one another in the extreme caseis extremely small.

For a somewhat harder material the motor shaft a and the shaft 0 of thesecond rolling ring a. may be coupled togeth v the toothed wheels ft andI2 as shown in gore 2.

For harder and thicker material ma" of advantage not to place therolling rings directly on the motor shaft but on shafts, which may bemounted separately and coupled with the motor shafts solely by aflexible joint. Such a construction is shown diagrammatically in Figure3 in which the shafts a and c of the two rolling rings 2) and d aremounted separately in roller bearings gi, g2, g3, g i and are coupledtogether by toothed wheels fl and f2. In this case the shaft a isconnected to the motor shaft 71, by a flexible joint and the motor isfixed to the supporting bed A by screws V and Vi.

Finally there is shown in Figure 4 a form of construction which enablesthe advantages of smaller rolling rings, driven directly at the samespeed as the driving motor without intermediate wheels, to be alsoapplied to thicker and harder material. The limit of using small rollingrings is defined to a lesser extent by the rolling rings themselves thanby the impossibility of making the bearings for the roller shaftssufiiciently strong so as to be capable of withstanding higher strains.If, however, the known principle of the six roll rolling mechanism isapplied in an analogous manner to the present constructional problemthis difficulty can also be overcome.

Figure 4; again shows rolling rings b and 02 mounted on the free ends ofthe shafts a and c which are coupled together by the toothed wheels fland it. The shaft o; is connected to the motor shaft'h by the elasticcoupling i. The bearing of the two roller shafts a and c is in thiscase, however, formed by four pairs of roller bearings GI, G2, G3, G5,G5, G6, Gl, Gil (of which G6 and G8 do not appear in the drawings). Thepositioning can be effected in a particularly convenient manner asindicated in Figure 5 in that the two roller shafts are mounted in twosupporting members ll and Z2 which are connected together by a hingelike link is these supporting members being capable of being movedtowards and away irom one another by the positioning screw m.

The construction of the rolling mill in which direct gearing fromdriving units as described mic-re is provided is more economical andcheap- 5 er than the construction of rolling mills in which separatetoothed wheel gean'ngs are provided outside the driving elements. Whenusing driving elements containing gearing the driving members can besimply screwed to a bed and if desired 10 may be removed rapidly andconveniently. When using separate intennediate gearing between thedriving element and the operating point it is necessary to providetoothed wheels outside the driving elements in the machine frame and to15 accommodate them exactly one to another, which makes the machineconsiderably more complicated and more expensive. According to thepresent invention the provision of this separate intermediate gear isomitted and the machine instead of containing three constructionalelements, the driving members, intermediate gearing and rolling rings,only contains two. This fundamental idea leads to a considerabletechnical simplification and thus to a reduction in cost 25 either whenthe rolling rings are coupled to simple motors as driving memb s o"ctheo'; wheel a shaft 3 drives Ve side.

rolling stations as cioseli another the gears under ranged above orbelow the electric motor so the overall width of the driving units be edon the bed is not larger than that of. trio motors themselves. Therolling "o be 45 placed on these driving units may be of largerdiameter, for example to mm.

According to the invention for the kind of con struction described firstthe various speeds of rotation of the separate rolling ring pairs,adapted to becombined so as to form a continuous rolling train, are notobtained the ":"i? of various toothed wheel gearings between t e drivingmotor and the rollers, but by diffs t numbers of revolution of theseparate dli members. In order to obtain the necessary adaptation of thenumbers of 11113110128 requirements of operation the motors of the dining members may either be of the ct; .ulativeiy wound compound type D'ued an resist: G3 ances in series In many cases a combination o boerable. For the second where the driving ele motors built together vdescribed above more i of the numbers of royal of rolling rings can bemotors of gradually increasing numbers of revo Iution all built togetherwith a constant standardized. simple or by using throughout the sametype of motor of them for the s number of revcluti as and bull ofconstrr oni electric 9,080,10l varying rrom stand to stand to meet thedesired i increase ,of speed.

The above description gives by way of example a iew forms ofconstruction of the essential fundamental idea. The details of thearrangement, mounting and coupling of the rolling rings may be carriedout in very diverse ways without departing from the scope of theinvention: i. e. to use for continuouswire rolling mills rolling ringsmounted on the free ends of the shaitsthe diameter of which is so smallthat they can be driven directly by the separate standardized drivingelements which are simply screwed to a bed. t

Although the costs of installation of a rolling mechanism according'tothe present invention, are less than those of the rolling mechanismsotherwise usual the driving members incase such a machine had to be putout .01 work prematurely have a much higher value'than those ofpreviously known rolling mills. In the case of the known arrangementsthe intermediate gears connecting the driving'motors to the rollingrings being separately in the framework oi the machine from the drivingmembers can be used advantageously only in the rarest of cases; As theseparately constructed intermediate gears in the known arrangements forman essential portion v of the costs of installation of the machine aconsiderable portion or the costs expended becomes practically valuelessif the machine is used no more whereas the driving members of rollingmechanisms according to the invention may be used profitably for anyother suitable purpose.

I claim: I

l. A continuous rolling mill for substantially reducing in thicknessrods and wires preferably for rolling soft material down tc'a diameterof l m. m. comprising a bed, a plurality of driving devices mountedthereon, each driving device including an electric motor and beingdetachable from the said bed as a whole, and a plurality of rollingrings mounted coaxially to the shafts of and directly driven by thedriving devices to cooperate with rolling rings mounted on separateshafts, the diameter or the said rolling rings being reduced to such anextent that usual rolling speed with commercial driving motors of 300 to3000 revolutions per minute is obtained, the said rolling rings beingcoupled by flexible joints with the motor shafts, the shafts of bothrolling rings being each journaled in two pairs of wide roller bearings,both pairs of roller bearings being situated on the same side of therolling rings and the adaptation of the various speeds of rotation ofthe separate rolling ring pairs in relation to one another beingeffected solely by electrically adjusting the speeds of the drivingmotors.

. 2. A continuous rolling mill for substantially reducing in thicknessrods and-wires preferably for rolling soft material down to a diameterof 1 m. m. comprising a bed, a plurality of driving devices mountedthereon, each driving device including an electric motor and beingdetachable from the said bed as a whole, and a plurality of rollingrings mounted coaxially to the shafts of and directly driven by thedriving devices to cooperate with rolling rings mounted on separateshafts, the diameter of the said rolling rings being reduced to such anextent that usual rolling speed with commercial driving motors of 300 to3,000 revolutions per minute is obtained, the said rolling rings beingcoupled by flexible joints with the motor shafts, the shafts of bothrolling rings being each journaled in two pairs of wide roller bearings,the axes of which are fixed in two brackets which are adjustablyconnected to each other by a hinge-like joint and the adaptation of thevarious speeds of rotation of the separate rolling'ring pairs inrelation to one another being effected solely by electrically adjustingthe speeds of the driving motors.

- WILHELM BOHN.

